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Diagnosis of Renibacterium salmoninarum infection in harvested Atlantic salmon ( Salmo salar L.) on the east coast of Canada: Clinical findings, sample collection methods and laboratory diagnostic tests
No full textChronic subclinical infection with the aetiological agent of bacterial kidney disease (BKD), Renibacterium salmoninarum, presents challenges for the clinical management of disease in farmed salmonids and for prevalence estimation. Harvested salmon sampled at processing plants provide the opportunity to describe subclinical outcomes of BKD using gross necropsy observations and diagnostic test results in farmed Atlantic salmon (Salmo salar L.) populations that are apparently healthy (i.e. alive at harvest) but naturally exposed to R. salmoninarum infection. Sampling of farmed salmon (Population A, n = 124 and Population B, n = 160) was performed immediately post-slaughter as fish were being processed at a plant in New Brunswick, Canada. Populations were selected based on planned harvests from sites with histories of recent exposure events related to clinical BKD as evidenced by the site veterinarian's diagnosis of mortality attributable to BKD: One site (Pop A) had recently increasing mortalities attributed to BKD, and the other site (Pop B) had ongoing low-level mortalities with BKD pathology. As expected with the different exposure histories, Pop A had a higher percentage (57.2%) of R. salmoninarum culture-positive kidney samples compared with similar fish samples in Pop B (17.5%). Diagnosis of R. salmoninarum by gross granulomatous lesions in internal visceral organs, bacterial culture and identification by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) using different swab transport methods, and molecular detection methods (quantitative PCR, qPCR) were compared. Agreement of culture-positive percentages at the sample level was moderate (kappa: 0.61–0.75) among specimens collected using different kidney sampling methods in Pop A and Pop B. The highest proportion of R. salmoninarum-positive cultures occurred when kidney tissues were transported to the laboratory and inoculated directly onto agar using a swab (94% of cultures from Pop A and 82% from Pop B when fish were positive by any culture method). Fish with cumulative lesion scores (severity of granulomatous lesions in 3 different visceral organs) of >4 were all culture positive, and when compared with non-lesioned fish, had substantially higher odds of being culture positive: Pop A: odds ratio (OR) = 73, 95% confidence interval (CI) (7.91, 680.8); Pop B: OR = 66, 95% CI (6.12, 720.7). Our study found that onsite postmortem examinations with severity scores of gross granulomatous lesions were predictive of positive culture results for R. salmoninarum, and they were a useful proxy for assessing prevalence in apparently healthy populations with subclinical infection.AVC Centre for Aquatic Health SciencesCanada Excellence Research Chai
Frequency of isolation and phenotypic antimicrobial resistance of fecal Salmonella enterica recovered from dairy cattle in Canada
No full textSalmonellosis is one of the leading causes of gastrointestinal infections in humans. In Canada, it is estimated that approximately 87,500 cases of salmonellosis occur every year in humans, resulting in 17 deaths. In the United States, it is estimated that 26,500 hospitalizations and 420 deaths occur every year. In dairy cattle, infections caused by nontyphoidal Salmonella enterica can cause mild to severe disease, including enteritis, pneumonia, and septicemia. Our study objectives were to determine the proportion of fecal samples positive for Salmonella in dairy cattle in Canada and determine the resistance pattern of these isolates. We used data collected through the Canadian Dairy Network for Antimicrobial Stewardship and Resistance (CaDNetASR). Pooled fecal samples from pre-weaned calves, post-weaned heifers, lactating cows, and manure storage were cultured for Salmonella, and the isolates were identified using matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Antimicrobial susceptibilities were determined using the minimum inhibitory concentration test, and resistance interpretation was made according to the Clinical and Laboratory Standards Institute. A 2-level, multivariable logistic regression model was built to determine the probability of recovering Salmonella from a sample while accounting for province, year, and sample source. The proportion of farms with at least one positive sample were 12% (17/140), 19% (28/144), and 17% (24/144) for the sampling years 2019, 2020, and 2021, respectively. Out of the 113 Salmonella isolates, 23 different serovars were identified. The occurrence of Salmonella appeared to be clustered by farms and provinces. The most common serovars identified were Infantis (14%) and Typhimurium (14%). Overall, 21% (24/113) of the Salmonella isolates were resistant to at least one antimicrobial. Resistance to tetracycline was commonly observed (17%); however, very limited resistance to category I antimicrobials (categorization according to Health Canada that includes third-generation cephalosporins, fluoroquinolones, polymyxins, and carbapenems) was observed, with one isolate resistant to amoxicillin/clavulanic acid. The proportion of Salmonella isolates resistant to 2 and 3 antimicrobial classes was 3.5% and 8.8%, respectively. Our study provided valuable information on the proportion of fecal samples positive for Salmonella, the serovars identified, and associated resistance patterns across CaDNetASR herds, at regional and national levels.Dairy Research Cluster 3 (Dairy Farmers of Canada and Agriculture and Agri-Food Canada)Public Health Agency of Canad
Pearl formation associated with gymnophallid metacercariae in Mytilus galloprovincialis from the Northwestern Adriatic coast: Preliminary observations
No full textGymnophallids of the genus Parvatrema are small trematodes infecting waterbirds in their adult stage. Several species of clams and mussels have been found to act as first and second intermediate hosts, in which the trematode larval stages induce the formation of pearls. In this study, a wild population of Mytilus galloprovincialis was sampled along the Northwestern coast of the Adriatic Sea to evaluate the origin and extent of visible pearls. Parasitological investigations, including morphological and molecular analyses, and histopathology were carried out on a representative sample of mussels (n = 158) from June to September 2021. The overall prevalence of infection reached 75.3 %, and the intensity of infection ranged from a few trematodes to thousands per mussel, mostly occurring in the mantle and surrounded by variable numbers of conchiolin layers. Morphological studies allowed classification of the metacercariae as belonging to the genus Parvatrema, and the pairwise comparison of the obtained sequences, encompassing the internal transcribed spacer (ITS) region, revealed a genetic similarity (96.8 %) to Parvatrema duboisi. However, the phylogenetic analysis demonstrated the independent clustering of the obtained ITS sequences compared to other available Parvatrema species. For the relevant commercial impact that pearl formation may have on farmed mussels, ecological and epidemiological aspects of this infection would deserve further investigation in the area
Advancing hydrochar production and application: A critical examination of microwave irradiation and blended feedstocks synergy
No full textSustainable and efficient hydrochar production via microwave-assisted hydrothermal carbonization (MW-HTC) and co-hydrothermal carbonization (co-HTC) has garnered increasing attention. This review offers a comprehensive analysis of recent advancements, primarily focusing on the performance and potential applications of hydrochar produced through these two processes. MW-HTC of lignocellulosic biomass yields hydrochar in the range of 30–80 dwt.%, with higher heating values of 19–23 MJ/kg and energy yields of 50–85%. Its adsorption capacity reaches around 50 mg/g for heavy metals and 1–5 mg/g for organic pollutants. Principal component analysis reveals significant differences in MW-HTC treatment of lignocellulosic and non-lignocellulosic materials. In the co-HTC process, sewage sludge and lignocellulosic biomass are the most studied feedstocks. Synergistic and antagonistic effects on hydrochar yield were identified, with most studies reporting a synergistic effect, particularly when protein and carbohydrate co-exist, potentially due to the Maillard reaction. The adsorption capacities of co-HTC hydrochars depend on the raw material mix, process parameters, and target contaminants. This review highlights the promising potential of MW-HTC and co-HTC for enhanced hydrochar production and application, emphasizing the necessity for future advancements, including machine learning for prediction of hydrochar yield, HTC process optimization, and feedstock's single model components-based HTC to elucidate the MW effect and synergism/antagonism.Natural Science Foundation of Fujian ProvinceFashu Research FoundationFujian Provincial Key Laboratory of Ecology-Toxicological Effects and Control for Emerging ContaminantsMinjiang Universit
Mechanism and performance evaluation of spent-coffee grounds-derived nanocomposite materials for highly efficient photocatalytic degradation of organic pollutant
No full textThe study demonstrates a facile and environmentally friendly method for synthesizing crystalline TiO2 nanoparticles on the surface of hydrochar generated from readily available biomass waste, i.e., spent coffee grounds (SCGs), using a simple sol–gel process. The hydrochar served as a support for TiO2, reducing the rate at which electrons and holes recombine during photocatalysis, thereby facilitating the effective binding of TiO2, enhancing its adsorption capacity, and the convenient separation of the photocatalyst after usage. The materials were tested in the photocatalytic degradation of an organic pollutant, methylene blue (MB) dye. TiO2-hydrochar obtained at 210 ⁰C has the best performance, giving a degradation efficiency of 98.5 % and a mineralization efficiency of 87.1 % in 90 min at neutral pH. Radical trapping experiments showed
being the dominant species, followed by
. Besides, it showed superior stability with an activity loss of ∼ 9.2 % after five runs. The superior performance of the HCT210 was ascribed to the enhanced interfacial charge transfer kinetics between the TiO2 and hydrochar through
bond formation, better light absorption, and the high surface area of the materials. Performance metrics show that synthesized nanocomposites are promising photocatalysts, providing a biomass-assisted method for robust photocatalytic wastewater treatment.Killam TrustsNatural Science and Engineering Research Council (NSERC
Bayesian analysis of diagnostic sensitivity and specificity for detecting infectious salmon anaemia virus (ISAV) using IFAT and real-time RT-PCR testing from laboratories in Atlantic Canada
No full textInfectious Salmon Anaemia virus (ISAV) is the causative agent of Infectious Salmon Anaemia (ISA), an economically important disease in farmed Atlantic salmon (Salmo salar L.). Immunofluorescence antibody test (IFAT) and real-time reverse transcription polymerase chain reaction (qRT-PCR) are commonly used diagnostic tests for ISAV active surveillance in Atlantic Canada; however, their diagnostic accuracy is not well reported. In the absence of a reference test, we used Bayesian latent class analysis methods to estimate diagnostic sensitivity (DSe) and specificity (DSp) of IFAT and qRT-PCR. We compared diagnostic performance of qRT-PCR, performed at two laboratories, and IFAT (performed at another laboratory) using field samples obtained from two separate salmon populations (total n = 130) in province of Newfoundland and Labrador, Canada. Conditional independence models for two tests (IFAT and qRT-PCR) and two populations (low and high prevalence) were run separately on datasets from each laboratory. Informative priors were used for DSe and DSp of qRT-PCR and IFAT based on prior knowledge, while flat priors (beta 1,1) were used for prevalence. qRT-PCRs had similarly high DSe (>91%). IFAT was the least sensitive method (DSe range, 56.9%–60.4%). Both IFAT (DSp > 98.8%) and qRT-PCRs (DSp > 97.9%) showed high DSp. Real-time RT-PCR provided the greatest DSe for routine surveillance of Atlantic salmon farms while not sacrificing DSp. Sample size for the study was not likely adequate to estimate all parameters with very high confidence, which could have influenced the posterior probability interval calculated for DSe, resulting in less diagnostic confidence in the results (posterior probability for Sensitivities for the tests within 10% of the true population value instead of 5%). Although IFAT provided a high DSp, the qRT-PCR performed similarly in this regard. The findings indicate that the qRT-PCR is fit for ISAV surveillance programs.Canada Excellence Research Chairs ProgramNewfoundland and Labrador Dept. of Fisheries, Forestry and Agriculture (NLFFA
The use of acceptance and commitment therapy among older adults in assisted living: a trend analysis and acceptability and feasibility study
No full textCanadian society is undergoing a major demographic shift in which a fifth of the population will be 65 years or older by 2024 (Garner et al., 2018). Professionals will need to become more adept at addressing this population’s mental health needs (Cairney et al., 2008). Prevalence rates of depression, anxiety, and chronic pain among older adults appear to vary by residential setting, with increased intensity of associated care associated with increased prevalence of mental health difficulties (Barbosa et al., 2014; Blazer, 2003; Creighton et al., 2015; Djernes, 2006; Fiske, 2009; Maxwell et al., 2013; Watson et al., 2003; Watson et al., 2006).
Assisted living facilities are ideal sites for intervention as residents’ mental health in this setting has serious implications for earlier discharge to nursing homes and even death (Watson et al., 2003). Group-based ACT interventions offer an effective and resource efficient solution to address this population’s needs. The present study examines the impact of group-based ACT on participants’ depression, anxiety, and chronic pain and examines the intervention’s acceptability and feasibility. Trend analyses were consistent with the anticipated reduction of anxiety and, to a lesser extent, depression. While the intervention appeared to be acceptable, there were significant challenges with feasibility, particularly with regarding recruitment. Implementing different recruitment strategies, including developing longstanding relationships with participating facilities and accepting referrals from potential participants’ treatment teams, may increase feasibility in future studies
Attachment style and children and young people with chronic dermatological conditions
No full textBackground
Dermatological conditions are common in childhood and, in their more severe forms, can cause pain, disability and social marginalisation. Despite attachment being a known factor contributing to psychological and physiological development in childhood and several adult studies showing associations between attachment and dermatology outcomes (Tomas-Aragones, 2018), attachment in young dermatology patients has not been investigated.
Objectives
This study examined if (1) 8–16-year-olds with chronic dermatological conditions were more likely to show attachment insecurity than general population peers; (2) attachment style was linked to psychological functioning; and (3) facial involvement was associated with attachment insecurity.
Method
One hundred and twenty-two 8–16-year-olds attending a specialist paediatric dermatological service were compared on the Child Attachment Interview (CAI) to general population data. The Strengths and Difficulties Questionnaire (SDQ) was used to measure psychosocial functioning.
Results
The dermatology group was significantly more likely to be insecurely attached than their general population peers (χ2[1] = 4.76, p < .05). The secure group self-reported significantly better psychological functioning on all indices compared with the insecure group (Total Difficulties: F[1,89] = 15.30, p < .001). There were no significant differences between secure and insecure groups on parent-reported psychological measures (Total Difficulties: F[1,94] = 0.67, p = .42). Children with facial involvement were not significantly more likely to be insecurely attached.
Conclusions
Increased risk of attachment insecurity, particularly in the anxious pre-occupied category, as well as an association between attachment and psychosocial functioning resonated with adult studies suggesting that further research about the role of attachment with young dermatology patients is warranted
Validation of a novel 3D printed positioning device and dynamic radiographic technique to quantify rotational laxity of the stifle in dogs
No full textCranial cruciate ligament deficiency (CCLD) results in internal rotational instability of the stifle (RLS). By contrast, tibial torsion (TT) is an anatomical feature of the tibia along its longitudinal axis. The objective of this study was to validate a dynamic radiographic technique to measure internal rotational laxity of the stifle and differentiate it from TT. Models included transection of the CCL for RLS and an osteotomy for TT. One limb within eight pairs of canine cadaveric hind limbs was randomly assigned to CCLD. The contralateral limb underwent TT, followed by CCLD. Neutral and stress radiographs were taken with the limb in a custom rotating 3-D printed positioning device before and after each modification. The position of the calcaneus on neutral views and the magnitude of its displacement under standardized torque were compared within limbs and between groups. Transection of the CCL increased the magnitude of displacement of the calcaneus by 1.6 mm (0.3–3.1 mm, p < 0.05) within limbs. The lateral calcaneal displacement (dS-dN) tended to be greater when CCLD limbs were compared to limbs with intact CCL. A magnitude of calcaneal displacement of 3.45 mm differentiated limbs with RLS from intact limbs with 87.5% sensitivity and 68.7% specificity. The calcaneus was displaced further laterally by about 3 mm on neutral radiographs (dN) when limbs with experimental TT were compared to those without TT (p < 0.05). A calcaneus located at least 3.25 mm from the sulcus differentiated limbs with TT from intact limbs with 87.5% sensitivity and 87.5% specificity. The technique reported here allowed detection of RLS, especially within limbs. A calcaneus located at least 3.25 mm on neutral radiographs of large dogs should prompt a presumptive diagnosis of TT.Western University of Health Science